Closure cap

ABSTRACT

A THIN METAL CAP FOR CLOSING CONTAINERS WITH NECKS HAVING AN UPPER COLLAR IN WHICH THE CAP IS FORMED WITH A BASE PORTION HAVING AN ELEVATED CENTRAL DISC, A TRUNCATED CONE JOINING THE OUTER EDGE OF THE CENTRAL DISC WITH A VERTICALLY DISPOSED SKIRT PORTION HAVING AN UPPER CYLINDRICAL PORTION AND A LOWER FRUSTOCONICAL PORTION WITH THE LOWER EDGE ROLLED INWARDLY THROUGH AN ANGLE OF 200* TO 250*.

Oct. 26, 1971 A. POYDESTA CLOSURE GAP 3 SheetsSheet 1 Filed May 14, 1969 FIG. 2

INVENTOR.

0 .w A Mmfl M w w W 1971 A. PODESTA CLOSURE CAP Filed May 14, 1969 3 Sheets-Sheet 2 3 Sheets-Sheet 5 A. PODESTA CLOSURE CAP Oct. 26, 1971 Filed y 14. 1969 FIG. 6

United States Patent 3,615,033 CLOSURE CAP Armando Podesta, Milan, Italy, assignor to Societe de Conditronnement en Aluminium Scal GP, Paris, France Filed May 14, 1969, Ser. No. 824,472 Int. Cl. B65d 41/10 US. Cl. 215-39 2 Claims ABSTRACT OF THE DISCLOSURE A thin metal cap for closing containers with necks having an upper collar in which the cap is formed with a base portion having an elevated central disc, a truncated cone joining the outer edge of the central disc with a vertically disposed skirt portion having an upper cylindrical portion and a lower frustoconical portion with the lowesroedge rolled inwardly through an angle of 200 to 2 This invention relates to a closure for containers having a collar in the neck portion and to an apparatus for the manufacture of same.

Use for such purpose can be made of a cap having a flat bottom forming the minor base of a frustoconical skirt which is provided with an S-shaped portion and which is terminated with respect to its major base by a rim or flange rolled inwardly through an angle of more than 400. Such cap has the disadvantage of being difficult to remove with conventional bottle openers. The prerolled rim is engaged and compressed by the opener such that considerable force is required to be applied, with the result that the collar of the container is often engaged and made subject to damage.

It is an object of this invention to provide a closure cap for containers having a collar in the neck portion, in which the cap is easy to remove with conventional bottle openers and is characterized by high resistance to internal pressure, and it is a related object to provide an apparatus for the manufacture of caps of the type described.

These and other objects and advantages of this invention will hereinafter appear and, for purposes of illustration but not of limitation, embodiments of the invention are shown in the accompanying drawings in which:

FIG. 1 is a sectional elevational view of a closure cap embodying the features of this invention for use on a container having a neck provided with a collar;

FIG. 2 is a sectional elevational view showing the cap of FIG. 1 in position of use on the container;

FIG. 3 is a sectional elevational view of a machine for making the cap with the elements in their relative position during the first stage of production;

FIG. 4 is a sectional elevational view similar to that of FIG. 3 showing the elements in an intermediate stage of production;

FIG. 5 is a sectional elevational view similar to that of FIGS. 3 and 4 showing the elements in their final stage of production to produce the finished cap; and

FIG. 6 is a sectional elevational view of an apparatus for automatic operation in producing the cap.

In accordance with the practice of this invention the cap is constructed, on the one hand, with a base having an elevatedcentral disc which forms the miner base of a truncated cone joined by its major base to a ring and, on the other hand, a skirt formed with an upper cylindrical portion and a lower frustoconical portion with an extension rolled inwardly through an angle of 200 to 250, the base and the skirt being joined by an intermediate semi-annular section which is concave toward the container.

The apparatus for manufacturing the cap comprises a first push rod having a central cylindrical portion and "ice a semi-annular peripheral portion with a flat annular groove therebetween, a second push rod with a central portion and a recessed peripheral portion joined by a projecting annular portion, a guide member through which the push rod is adapted to slide and which is formed at its upper end with an open space defined by two cylindrical sections the base of which is formed by a ring limited to two quarter inner and outer annuli, and a punch which surrounds the second push rod and which is designed to be received in the open spaced of the guide member.

Referring now to the drawings, the cap 1 for closing a container 2, having a collar 21 (as shown in FIG. 1) comprises a base 11 and a skirt 12 joined by an intermediate section 13.

The base 11 is in the form of an elevated central disc portion 111 which forms the minor base of a truncated conical section 112 which terminates at its major base at the lower end in a flat outwardly extending ring 113.

The skirt 12 is formed of an upper cylindrical portion 121 and a lower frustoconical portion 122 having an extension turned inwardly through an angle within the range of 200 to 250 to define the rolled section 123.

The intermediate section is in the form of a semiannulus 13 which is concave toward the containeri.e., toward the base. The intermediate section joins the outer periphery of the flat ring 113 to the upper end of the cylindrical portion 121 of the skirt and from which it extends in an upward direction.

The closure is provided with a sealing compound 14 which, for example, may be injected into the intermediate semi-annular zone 13 and spread to extend over the upper end of the roll 123. The positioning of the closure requires a proper drawing operation, as shown in FIG. 2, wherein the skirt is drawn downwardly until the lower rolled portion 123 is displaced to beneath the collar 21 which is engaged in response to the effect of lateral pressure applied toward the axis 22 of the container. The intermediate portion 13 provides a reserve which enables the longest part of this extension of the skirt to undergo further elongation by reason of the elasticity of the metal. The intermediate portion of the cylindrical section 121 of the skirt is deformed by engagement against the upper part of the collar 21 and the sealing compound 14 is flattened by flow between the cap and the collar.

The shape given to the lower roll 123, which is not integrally pushed back beneath the collar, enables the cap to be gripped and removed by means of a conventional bottle opener without any difficulty and without any risk of damage to the collar.

A cap of the type described, made from a sheet of aluminum alloy containing 2% magnesium and having a thickness of 0.2 mm., can withstand an internal pressure of 15 bars. In addition, a limited number of metal sheets need be used for the cap.

The machine 3 for making the cap comprises a first push rod 31, a second push rod 32, a guide member 33, and a punch 34.

On its upper surface, which forms the pressure surface, the first push rod 31 is formed with a fiat central portion 311 in the form of a raised cylindrical section and a semiannular peripherally spaced ring 313 joined by a flat annular recessed or grooved portion 312. The peripheral portion 313 extends to a higher level than the central portion 311. The lateral surface 314 of the push rod is cylindrical to define a push rod of cylindrical shape.

On its lower surface, which represents the pressure surface, the second push rod 32 is formed with a fiat central section 321 in the form of a cylindrical recessed portion dimensioned to be greater in diameter than the portion 311 of the first push rod and in axial alignment therewith. An

annular peripheral section 323 is spaced outwardly of the section 321 and is joined thereto by an integral intermediate annular section 322 which extends downwardly or forwardly beyond the base of the section 321. The depth of the central portion 321 and the depth of the peripheral zone 323 relative to the intermediate section 322 are respectively about equal to the height of the central portion 311 and to the height of the peripheral portion 313 of the punch 31.

When the two push rods are brought into contact, the central portion 311 of the punch 31 projects into the central zone 321 of the push rod 32 with the latter being wider than the former. The peripheral portion 313 similarly enters the peripheral zone 323 which is of slightly greater width, the difference being substantially equal to the thickness of the metal of the cap.

The guide member 33 is formed with a hollow lower section 331 having an internal diameter slightly greater than the external diameter of the first push rod 31 to enable relative axial movement therebetween. The guide member 33 is formed with a similarly hollow upper portion 332 of greater internal diameter to provide an annular space 333 between the upper portion 332 and the push rod 31, as limited by the two concentric vertical cylinders. The bottom of this open space defines a ring 334 of circular shape limited by two quarter annuli 3341 and 3342 on the outside and inside respectively.

The punch 34 surrounds the push rod 32. At its base, it is formed with a frustoconical surface 341 which forms an angle 3410 of more than 50 with the axis 22.

The cap is made from a blank having a base 101 in the form of a disc and a cylindrical skirt 103, with the upper end of the skirt joined to the outer edge of the disc by an intermediate portion 102 in the form of an inverted U-shaped section the arms of which are oblique with the longer arm being joined to the skirt.

In the starting position, the push rod 31 is in its upper position in which it does not touch the second push rod 32, and the punch is raised, as shown in FIG. 3. The blank is placed in position with the base between the push rods and the skirt extending into the open space 323. The skirt is dimensioned so that it does not extend to the bottom of the open space.

The unit, comprising the push rod 32 and the punch 34 is then displaced in the downward direction parallel to the axis 22. The bottom of the blank is gripped between the two push rods 31 and 32 which impress upon the blank the parts 111 and 113 and the lower portion of the intermediate section 13. The push rods continue to descend together and, as the lower end of the skirt 103 engages the curvilinear bottom of the open space 333, it is rolled inwardly in response to displacement against the quarter annuli 3341 and 3342. Upon completion of the rolling, the push rods lock and the punch continues to descend, as shown in FIG. 5. The lower surface 341 of the punch imprints on the blank the outer portion of the intermediate zone 13 and the cylindrical portion 121 and flattens the outer portion 122.

These various movements can be achieved in a single operation with the more elaborate'apparatus shown in FIG. 6, which may be provided with automatic controls.

The punch 34 is kept in its upperpositon relative to the push rod 32 by a spring 35 confined in a compressed state Within an annular space 351 with the upper end of the spring 35 engaging a ledge 352 of the punch and with the lower edge of the spring 35 engaging a ledge 353 of the push rod 32. The push rod 31 is kept in its upper position relative to the guide member 33 by a coil spring 36 confined in a compressed state within an annular space 361, with the uper edge of the coil spring 36 engaging a ledge 362 of the push rod 31 while the lower edge of the spring 36 rests upon a ledge 363 of the guide 33. In addition, the movement of the push rod relative to the guide member is limited by stops in the form of ledges 335 integral both with the latter and 315 with the former. The spring 35 has greater compression than the spring 36.

In operation, all that is necessary is to actuate the punch. The punch, which is moved downwardly along the axis 22, drives the push rod 32. The blank is gripped between the two push rods. As downward movement continues, the push rod 31 is displaced downwardly with the push rod 32, compressing the spring 36'. The portion 123 of the skirt continues to be rolled until the stops 315 and 335 come into contact to militate against further downward movement of the push rods. At this time, the punch 34 continues to move downwardly alone with corresponding compression of the spring 35. This second downward movement can be limited by stops 345 and 325 similarly arranged as the stops 315 and 335 to the push rod and punch respectively.

It will be apparent from the foregoing that We have provided a simple and efficient apparatus for use in the manufacture of new and novel sheet metal closures which are capable of effecting a strong sealing closure of bottles having a collar in the neck portion and which are capable of easy removal with conventional tools.

It will be understood that changes may be made in the details of construction, arrangement, and operation without departing from the spirit of the invention, especially as defined in the following claims.

Iclaim:

1. A closure for containers having a collar in the neck portion comprising a base portion and a skirt portion in which the base portion is formed with a central disc section, an outer, downwardly extending truncated cone having its minor base joined to the outer edge of said disc section, and a fiat ring outwardly from the major base of the truncated cone with the major base of the truncated cone joined to the inner edge of the flat ring, and in which the skirt portion comprises an upper cylindrical section and a lower frustoconical section with the lower edge of the frustoconical section rolled inwardly, and a concave semi-annular intermediate section extending above the base portion and joining the outer edge of the flat ring of the base portion with the upper edge of the cylindrical skirt portion.

2. A closure as claimed in claim 1 in which the rolled edge at the bottom of the frustoconical section is turned inwardly through an angle within the range of 200 to 250.

References Cited UNITED STATES PATENTS 3,497,097 2/1970 La Barge et a1. 215-39 FOREIGN PATENTS 637,576 9/1963 Belgium 215-39 GEORGE T. HALL, Primary Examiner 

